1. Global Winds

2. Atmospheric Pressure  Wind is caused by differences in air pressure around earth’s surface.  Differences in air pressure are due to the unequal heating of the earth’s surface.  A warmer surface has air rising over it as compared to a cooler surface that has air sinking over.

3. Atmospheric Pressure  Warm air is less dense than cooler air, so warm air has the tendency to rise above cooler more dense air.  As a result warm air rises and cool air sinks.  When warm air rises cold air flows in to take its place creating wind.

4. Atmospheric Pressure  The earth is always trying to reach equilibrium with regards to temperature.  Since the earth receives unequal heating it will never reach an equilibrium so the wind will always blow.

5. Sun Angles  Areas on and around the equator receive more direct concentrated sun.  As you approach the poles the concentration of sun gets weaker.

6. Single cell Model Hadley Cells

7. Three cell model

8. Coriolis Effect

10. Global Winds